Hi! Im switiching my BCP in the next week or so. I was told by my doc to start it on the Sunday i get it my period, if you get it on Sunday, take it that day. I was told not to wait for 7 days cuz it may cause excess bleeding. And remember from switching from one BCP to another, the first few months are sometimes bad for some people, meaning you may get extra cramps and spotting. I would call your doctor to make sure, he may want your body to detox for 7 days tho. Good luck.